AC Regulator Danger: Is There Risk?

[Krakadoros]

Is there a danger from AC regulator, for human ? There is one, plugged on the wall's AC socket. On the top has a plastic accessory with two metall parts. These metalls are grounded. Is there a danger for somebody who touch these metals, when for example a thunder hit the ground, or something else (i cannot imagine now) will happen to the ground of the building (5th floor) ?
thanks

 

[davenn]

hi there
welcome to PF :)

can you show a pic of the plugpack you are referring to please
I am unaware of ones with exposed metal tabs

Dave

 

[Krakadoros]

I told that these metal accessories are grounded, because if an object, which have voltage at the two ends, touch one of these metals (or both), the voltage decrease dramatically, near to zero. How i know this? I measured it. How i measured it ? With a volt meter. I assumed that this is because of it is grounded. I am not an electrician. So my first question have two sub questions. 1)If somebody is connected to the ground, or touch a metal pipe which is grounded, is there a danger ? (from a thunder or something else i cannot imagine) 2) Are these metals grounded ? Is there a method different than mine, to determine it (maybe open the box to see what is inside)?

 

[davenn]

Ok that makes it clearer
you are talking about the carry handle mounts ... it initially seemed because of your description that you were referring to electrical connections

OK, I'm assuming this is some sort of power supply, those mounts are metal, they connect to a metal case. That metal case SHOULD be connected to the mains power earth.

1)If somebody is connected to the ground, or touch a metal pipe which is grounded, is there a danger ? (from a thunder or something else i cannot imagine)

a direct lightning strike on the power lines outside or near your home may or may not liven the case and tabs briefly
I have repaired a lot of lightning damaged equip over the years and the one thing that I have learned is that lightning is totally unpredictable
in the way it travels through things and the damage it does
If I have the chance, I will often unplug TV's power and antenna, my amateur radio gear. Never use a cord connected phone during a thunder storm,
mobile (cell) phones are OK

2) Are these metals grounded ? Is there a method different than mine, to determine it (maybe open the box to see what is inside)?

As I said above, they should be grounded, firstly, without opening the case, and using an test meter in resistance range. Unplug the power supply from the wall. Put one meter probe on one of the tabs put the other one on the Earth pin of the power plug ... you should read somewhere around zero to a couple of Ohms. That will confirm if it is grounded

if so, that's good ... any western country should have electrical laws that govern that sort of thing

the other time it could be a danger would be if that grounding system became open circuit and IF by chance a fault developed in the power supply that made the case live to mains power.
Then you could get an electrical shock

Dave

 

[Krakadoros]

Dave, thanks for your reply. I check the regulator the way you told me, and I found 0.3 Ohms. This means that metals are grounded and there is a possibility for me to receive a shock, small possibility, but there is. I notice that in the electric board of my house, there is a test button, and I think it is to check a system, that detects leakages. It is a label on it with FH202 AC, 40A IΔn=0,03A, Un=230V, Im=IΔm=1000A, 63A, 6000 . I think that this system will turn off the current if there there will be something on 30mAmpere, but I do not know how it is work. Do you know how it is work and do you think that it can protect me? There is something else that can protect me: I connect the metals with an aluminum foil and I lay my legs on it, for the voltage I receive in my body goes away from me. (this really happens because I measured it. And with all these devices that surround me (laptop, 24” screen, 4 speakers, a stage piano, etc.), I have much of volts on me (3-6volts) which all goes away if I lay my legs on aluminum foil which is connected with the metals (which are grounded.) The connection between the metals and the foil is made by a small copper wire. This wire can be a fusion. The regulator itself has a fusion, but is 5 ampere. I need a 25mAmpere or at least 30mA to protect me. So if there is a material that have two characteristics: 1)to allow current and 2)to break itself, when 25-30 mAmperes goes through it, then I can use this material to connect the metals with the foil. Do you know any kind of this material or any other “patent” to connect the foil with the metals?

Note : Believe it or no, the most volts I receive, is from the surge (with 5 sockets) even it is turned off. The only way not to “operate” volts towards me, is to unplugged it.